Peptide-conjugated nanoparticles for targeting, imaging, and treatment of prostate cancer

Abstract

An isolated or a synthetic targeting peptide comprising an amino acid sequence that is at least 90% identical to SEQ ID NO: 8 is disclosed. The targeting peptide may be conjugated to a component selected from the group consisting of polymeric micelles, lipoprotein-based drug carriers, nanoparticle drug carriers, a chemotherapeutic agent, a micelle, a liposome, dendrimers, a polymer, a lipid, an oligonucleotide, a peptide, a polypeptide, a protein, a prostate cancer cell, a stem cell, and an imaging agent. Also disclosed are a kit for imaging and detecting the presence of prostate cancer cells in vivo or in vitro, and a composition for treating prostate cancer, inhibiting prostate cancer cell growth, inducing prostate cancer cell cytotoxicity, and/or increasing the survival rate in a prostate cancer patient.

What is claimed is: 
     
       1. A conjugate comprising:
 (a) an isolated or a synthetic targeting peptide comprising an amino add sequence that is at least 90% identical to SEQ ID NO: 8; and 
 (b) a component, to which the targeting peptide is conjugated, the component being selected from the group consisting of polymeric micelles, lipoprotein-based drug carriers, nanoparticle drug carriers, a chemotherapeutic agent, a micelle, a liposome, dendrimers, a polymer, a lipid, an oligonucleotide, a peptide, a polypeptide, a protein, a prostate cancer cell, a stem cell, and an imaging agent, 
 wherein the component is not an M13 phage. 
 
     
     
       2. The conjugate of  claim 1 , wherein the targeting peptide is conjugated to:
 (a) the chemotherapeutic agent; 
 (b) the oligonucleotide; 
 (c) the imaging agent; or 
 (d) the liposome. 
 
     
     
       3. The conjugate  claim 2 , wherein the component is a PEGylated liposome. 
     
     
       4. The conjugate of  claim 2 , wherein the imaging agent is selected from the group consisting of quantum dots, superparamagnetic iron oxide nanoparticles, and a fluorescent dye encapsulated within a liposome. 
     
     
       5. The conjugate of  claim 1 , wherein the component is the liposome, and the conjugate further comprises one or more anti-cancer agents encapsulated within the liposome. 
     
     
       6. The conjugate  claim 5 , wherein the component is a PEGylated liposome. 
     
     
       7. The conjugate of  claim 1 , wherein the targeting peptide consists of less than 20 amino acid residues in length. 
     
     
       8. The conjugate  claim 7 , wherein the component is a PEGylated liposome. 
     
     
       9. The conjugate  claim 1 , wherein the component is a PEGylated liposome. 
     
     
       10. The conjugate of  claim 1 , wherein the component is the imaging agent that is selected from the group consisting of quantum dots, superparamagnetic iron oxide nanoparticles, and a fluorescent dye encapsulated within a liposome. 
     
     
       11. A method for imaging and detecting the presence of prostate cancer cells in vivo or in vitro, comprising:
 (a) providing the conjugate of  claim 10 ; 
 (b) causing the prostate cancer cells to be exposed to the conjugate in vitro or in vivo, 
 (c) allowing the targeting peptide of the conjugate to bind to the prostate cancer cells in vitro or in vivo; and 
 (d) performing imaging to detect the presence of the prostate cancer cells in vitro or in vivo. 
 
     
     
       12. A kit comprising:
 (a) the conjugate of  claim 10 ; and 
 (b) a written instruction for use of the kit in imaging and detecting the presence of prostate cancer cells in vivo or in vitro. 
 
     
     
       13. An isolated or a synthetic targeting peptide comprising an amino acid sequence that is at least 90% identical to SEQ ID NO: 8 and that is conjugated to a component selected from the group consisting of a liposome, a PEGylated liposome, a nanoparticle, or an imaging agent, wherein the component is not an M13 phage. 
     
     
       14. The targeting peptide of  claim 13 , comprising the amino acid sequence of SEQ ID NO: 8. 
     
     
       15. The targeting peptide of  claim 13 , consisting of less than 20 amino acid residues in length. 
     
     
       16. The conjugate of  claim 13 , wherein the imaging agent is selected from the group consisting of quantum dots, superparamagnetic iron oxide nanoparticles, and a fluorescent dye encapsulated within a liposome. 
     
     
       17. A composition comprising:
 (a) liposomes; 
 (b) a therapeutically effective amount of one or more chemotherapeutic agents, encapsulated within the liposomes; and 
 (c) an isolated or a synthetic targeting peptide comprising an amino acid sequence that is at least 90% identical to SEQ ID NO: 8, being conjugated to the surfaces of the liposomes. 
 
     
     
       18. The composition of  claim 17 , comprising two or more different chemotherapeutic agents with each chemotherapeutic agent being separately encapsulated within the liposomes. 
     
     
       19. A method for treating prostate cancer, inhibiting prostate cancer cell growth, inducing prostate cancer cell cytotoxicity, and/or increasing the survival rate in a prostate cancer patient, comprising:
 administering an effective amount of the composition of  claim 17  to the prostate cancer patient.